Improved marine-propeller



UNITE i STATES- PATENT EEIcE.

WILLIAM D. WILsoN, or NEWARK, NEW JERSEY.

IMPROVED MARINE-PROPELLER.

ZZ whom fit may concern:

ne it known that I, WILLIAM D. WILsoN, of Newark, in the county of Essexand State ofNew Jersey, have invented certain new and usefulImprovements in Instruments for Marine Propulsion; and I do herebydeclare that the following is a full, clear, and exact description ofthe same, reference being had to accompanying drawings, making a part ofthis specification, and to the letters of reference marked thereon.

The means commonly used for applying the power for marine propulsionhitherto have each had peculiar disadvantages, by which a portion of thepower has been wasted. action of the paddle-wheel, by which the paddleat the moment of entering` and leaving the water, at an angle offorty-five degrees, for instance, has involved a loss of half the powerapplied at those points, is a familiar example, and the remedy that hasbeen applied to this waste of power by the radial wheel, consisting ofvarious appliances for causing the paddle to enter and leave the waterin a vertical direction, has also been found useless in oceannavigation, which necessarily includes the conditions of varying anddeep immersions, as may be simply illustrated by the eXtremeconsideration of immersion to the shaft when it is obvious that theentering paddle would not only be of no propulsive value, but wouldoppose its entire area to the progress of the vessel. In a similarmanner the various patterns of the screw-propeller designed tocounteract or avoid the losses of power incident to angular andcentrifugal action, friction of the helicoidal surface, interference ofthe blades or the arms carrying the blades, and other causes of loss ofpower, have been and are still so numerous and different that in theaggregate they fully indicate that the instrument itself must be foundedupon an incorrect principle.

The object of my invention is to apply the propelling power of a vesseldirectly in the line of progress without radial or angular action, andin such a manner that the direction ofmotion may be instantly and easilyreversed.

To accomplish the rst feature of this object, my inventionn consists inmounting upon a shaft that extends from the vessel parallel to the keela pair of vanes that are at right angies to the shaft and oppose theirentire area The radial to the water, when projected backward, and thatcollapse toward the shaft, and present only their edges when the shaftis withdrawn to the vessel in preparation for another stroke. If theshaft of the propelling-vanes be attached directly to the piston of theengine, the steam on the forward side of the piston reacts in arectilinear directionagainst the water, behind the open faces of thepropelling-vanes, and thus forces the vessel ahead with only the slightloss of power due 4to the friction-of the piston and piston-rod orshaft, and in making the return-stroke the vanes collapse or turn backtoward the shaft so as to present merely their edges in passing throughthe water; and to enable the direction of the propulsion to be changed,the stops that prevent the vanes opening` beyond aright angle to theshaft are placed on a secondary shaft, by which they may be turned, sothat they pass between the vanes instead of extending behind them. Byturning this secondary shaft one-quarter way round, therefore, theoutward stroke of the propelling-shaft causes the vanes to collapseforward toward the shaft, and the return-stroke, that retracts theshaft, again opens the vanes until they arrive at right angles to theshaft, when they strike upon another pair of stops similar to those rstv entioned and placed upon the same shaft. A quarter-turn of thissecondary shaft, therefore, determines the direction of the opening andthe consequent action of the propelling-vanes.

'Io enable others skilled in the arts to which it appertains to make anduse my invention, I will proceed to describe its construction andoperation with reference to the drawings.

Figure l is a side elevation of the instrumeut or apparatus placed underone of the quarters of a vessel, as indicated by the marginal line; andFig. 2 is aplan of the same. The dotted black lines show the positionassumed by the vanes when the propeller is retracted, and the red linesindicate the position of the parts when it is prepared for backing.

The head of the propeller-shaft a carries the vanes b b by the joints orpivots c c, so that the vanes are each lfree to swing through thesemicircle outward from the shaft.

The supplemental or reversing shaft d is free to turn through aquarter-circle in the head of the propeller-shaft by which it iscarried, and it is provided with the stops e and f, placed at rightangles with each other and firmly secured in such a manner that whentheir Shaft is turned a quarte-r round they will either extend behindthe vanes or lie between them. As represented by the black lines in thedrawings, the stop e prevents the vanes swinging forward on the shaft,and consequently when the shaft is thrust outward from the vessel thevanes are held open by the stop and react against the water for thepropulsion of the vessel; but when the shaft is retracted they Swingback toward it and lie in the line of progression. In a similar manner,as represented in red lines, when it is desired to back, the aftermoststops f may be turned across the vanes, so that the latter are supportedor restrained when the shaft is retracted, and are collapsed when it isforced outward.

As the propelling-vanesthus naturally adapt themselves to present merelythe slight resistance of their edges to the water when they are not inuse, this instrument has the important advantage of offering but littleresistance when the vessel is under sail alone, and does not require,therefore, any apparatus similar to that sometimes applied with thescrew to hoist it out of water, and there is no necessity for removingany of its parts like there is for taking off the immersed paddles ofwheels.

Having thus described and illustrated the character of my invention, Iwould remark that Where a higher speed of the vessel is desired thanwould be consistent with the speed ofthe piston, the propellingshaft maybe driven from the outer end of a lever, to which the engine isconnected at an intermediate point,l

of a lever or beam, so that one of them may be thrusting while the otheris being` Withdrawn, by which arrangement the power may be uniformlyapplied in the forward and return strokes of the engine.

Instead of hanging the propelling-vanes by joints or pivots placed nearto one edge, they may be hung but a little out of the center, so thatthere may be but sufficient preponderance on one side to insure theiropening properly.

By this means also a large portion'of the l strain may be removed fromthe stops and rel versing-shaft to the main propelling-shaft.

. The reversing-shaft carryingy the stops may l be turned to 'reversethe motion of the vessel by a hand lever or gearing, or in any otherconvenient manner, and both shafts maybe projected astern of thepropeller to rest insuitable supports affixed to the stern-post or'otherconvenient part of the vessel for that purpose. I claim as my inventionand desire to. secure by Letters Patent- The combination of thepropelling shaft and vanes and the reversing shaft and stops,substantially as described.

W. D. WILSON.

Witnesses:

THOMAS DAY, WM. KEMBLE HALL.

